Generally, container known as a spout-pouch container is suitable for containing a jelly beverage. For example, one spout pouch container has a bag-like container main unit having a flexible sheet that has a spout of rigid resin heat sealed thereto. (See Japanese Kokai Publication Hei-2004-29970.) In use, the consumer pushes the flexible sheet to squeeze out the jelly beverage from the spout. In addition, the spout pouch container has been designed so as to stand erect in cooler cases found in stores. (See Japanese Kokai Publication Hei-2006-219157.)
Also, plastic bottles, for example, PET bottles, store products having comparatively low viscosities, for example, water, tea, carbonated beverages, juices, and the like. Bottles containing those low viscous fluids have been widely marketed and have been sold at retail stores and in automatic vending machines. However, plastic bottles containing products having comparatively high viscosities such as jelly beverages, which are squeezed to be dispensed for drinking, have not been marketed.
Plastic bottles that can be folded up after use for waste recovery and plastic bottles whose volume before filling can be temporarily reduced for efficient stacking and shipping have been available. For example, a plastic bottle can be formed with soft walls and rigid walls, alternating in the circumferential direction, so that sections of the shoulder, body, and base having soft walls would fold inward after use. (See Japanese Kokai Publications Hei-8-24474 and Hei-10-230919.)
However, the base of plastic bottles readily hardens due to the molding method. For example, when producing plastic bottles using stretch blow molding, the base of the bottle becomes hard after molding because the base of the preform is stretched using a rod. When the base becomes hard, bending of the base becomes difficult or a clean fold becomes impossible even if it could be bent, and a comparatively large space remains at the bottom of the bottle. For this reason, even if a jelly beverage is packed in a bottle, it is difficult to dispense all or a substantial portion of the jelly beverage that remains at the bottom of the bottle.
Thus, there remains a need to provide a plastic bottle that allows the main unit to bend without bending of the base, thereby allowing products having a comparatively high viscosity to be removed from the base.